Beverly Young Nelson on Monday accused Roy Moore, a Republican Senate candidate for Alabama, of groping her and trying to force her to perform oral sex on him when she was a 16-year-old high school student and he was a 30-year-old lawyer.

Shortly before Nelson's made the allegations, Mitch McConnell, the Republican Party (GOP) leader of the US Senate, called on Moore to withdraw from the race. Nelson is the fifth woman to level allegations of sexual misconduct against Moore.

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McConnell said, "I believe the women," referring to allegations made by four women last week who have accused Moore of pursuing sexual relationships with them when they were under-aged-teenagers.

Leah Corfman told US newspaper The Washington Post last week that she was a 14-year-old girl when Moore initiated sexual contact with her in 1979. Moore was 32 years of age at the time.

Three other women spoke on-the-record to the Post, accusing Moore of making sexual advances when they were each minors.

When the story came out last week, McConnell said Moore should withdraw from the senate race if the allegations prove true.

'Witch hunt'

But Moore, a former judge and an evangelical Christian, maintains that the allegations are false while calling on McConnell to resign.

"The person who should step aside is Senate Majority Leader Mitch McConnell," Moore tweeted in response to McConnell's call.

Moore said McConnell is part of the proverbial Washington "swamp" that US President Donald Trump campaigned against.

Despite Moore's claims that the allegations against him are a "witch hunt," pressure is growing for him to step aside.

GOP Senator Susan Collins of Maine joined McConnell in calling for Moore to withdraw, saying she found his denials unconvincing.

More damaging for the embattled candidate, GOP Senator Cory Gardner, who leads the Senate Republican campaign effort, called Moore unfit to be a senator.

"If he refuses to withdraw and wins, the Senate should vote to expel him, because he does not meet the ethical and moral
requirements of the United States Senate," Gardner said in a statement.

Moore is also threatening to sue The Washington Post, which corroborated its story with more than a dozen sources — in addition to the four primary accusers who were all identified by name.

The race tightens

While Moore has called the allegations "completely false and misleading," he raised concerns among Republicans during an interview with conservative radio host Sean Hannity when he did not categorically rule out dating teen-aged girls when he was in his 30s.

Asked if that would have been usual for him, Moore said, "Not generally, no."

Alabama is a deeply conservative state, and Moore had a comfortable lead in polls, ahead of the special election slated for December 12 — until the sex abuse allegations broke last week. A series of new polls suggest Moore is now in a neck-and-neck race with his Democratic opponent Doug Jones, a former US District Attorney.

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More troubling for Moore is the prospect of another republican entering the race as a write-in candidate, which McConnell has suggested is a possibility.

"That's an option we're looking at ... whether or not there is someone who can mount a write-in campaign successfully," McConnell said Monday. Asked specifically about current Sen. Luther Strange, who lost to Moore in the GOP primary, he said, "We'll see."

With the election now less than a month away, Moore's name will likely be on the ballot whether he withdraws from the race or not. A third candidate, running as a write-in would be a long-shot bid to win — giving the Democrats their best chance to recapture a seat they haven't held in 20 years.

bik/rt (AP, Reuters, AFP, dpa)